Automatic train control



Feb. 17; 1925. 1,526,750

F. T. KNIGHT AUTOMATI C TRAIN CONTROL Filed Dec. 30, 1922 4 Sheets-Sheet 1 SAFETY NORMAL RUNNIN (1' PO SIIION 155 6 AIR BRAK IL LINE compnassan Am INVENTOR I A TTORNEKS 62/ J Feb. T]. 1925. 1,526,750

F. T. KNIGHT AUTOMATIC TRAIN CONTROL Filed Dec. 30, 1922 4 Sheets-Sheet 2 s asm olMxwsHma POSITION AIR BRAKE LINE COMPRESfiED AIR,

Feb. 17. 1925.

F. T. KNlGHT AUTOMATIC TRAIN CONTROL 1 MWW 1 Q: I 2 A Wv & w 1 0 5 C. e D d e l. 1 F

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Patented Feb. 17, 1925.

FRANK TALLIAFERRO KNIGHT, 0F MACON, GEORGIA.

AUTOMATIC TRAIN CONTROL.

Application filed December 30, 1922.

To all whom it may concern:

Be it known that I, FRANK TALLIAFERRO KNIGHT, a citizen of the United States, and a resident of Macon, in the county of Bibb and State of Georgia, have invented certain new and useful Improvements in Automatic Train Controls, of which the following is a specification.

My invention relates to improvements in train controls, and it consists of the-constructions, combinations and mode of operation herein described and claimed.

An object of the invention is to provide apparatus for automatically either stopping a train or diminishing the speed thereof in accordance with the nature of the signal set against it as it enters a block.

Another object of the invention is to provide an automatic train control wherein the speed diminishing mechanism acts inde pendently of the stopping mechanism.

A further object of the invention is to, provide an automatic train control of the closed circuit type which is so-called on account of the various electrical circuits being closed during the normal and safe operation of the train and opened upon the occurrence of a mal-operation, for example, a short circuit, a grounded connection, a broken wire, failure of electric current, etc.

A further object of the invention is to pro vide a train control comprising two series of clectiomagnets in the track element, one

series controlling the diminishing of the speed, the other controlling the stopping of the train, and an arrangement of cooperating armatures comprising the trainelement, which armatures have associated fluid actuated devices arranged to operate in such a manner as to control the speed of the train, the aforesaid electrical devices being normally energized to prevent the operation of said fluid-actuated mechanism until any one of the previously mentioned mal-operations occurs.

Other objects and advantages will appear in the following specification, reference being had to the accompanying drawings, in which:

Fig. 1 is a diagram illustrating the automatic train control apparatus in the normal running position,

Fig. 2 is a similar diagram illustrating the operations which occur either when a can- 'tion signal is set against the train and the Serial No. 610,024.

engineer attempts to run past without reducing the speed, or when the train approaches a crossing or other dangerous point,

Fig. 3 is a diagram illustrating blocks A, B and C, showing the occurrences upon the presentations of the various signals safety, caution and danger,

Fig. 4 is a detail perspective view of one of the armature boxes carried by the engine,

Fig. 5 is a detail cross section on the line 55 of Fig. 4,

Fig. 6 is an elevation (parts in section) of one of the semaphore switches which controls the track element,

Fig. 7 is a detail cross section on the line 77 of Fig. 6, and

Fig. 8 is a detail section of the air vent the train. Any interruption of such circuits will cause an immediate response of the various control devices and so either diminish the speed of the train or stop 1t outright.

The construction.

The control apparatus comprises the throttle valve 1 which controls the admission of steam from the dome 2 into the pipe 3. The throttle valve has a connection 4; which runs back into the cab of the engine 5 where it joins the lever 6, The detent of this lever works over a quadrant, and the obvious purpose of the arrangement is to fix the adjustment of the throttle valve, such adjustment controlling the passage of steam to the chest 7. The valve mechanism (not shown) of this chest in turn controls the admission of steam to the cylinder 8.

On entering the pipe 3, the steam must pass through the main steam valve 9 before it reaches the steam chest. The main steam valve 9 is operated on only two occasions, namely, when the control apparatus operates to either diminish the speed of or stop the train. The stem 10 of the valve hasa handle 11 Which is adapted to be engaged by the roller 12 on the rod 13 of the piston 14 in the valve cylinder 15'. Airis adm'itted'at the left of this cylinder to drive the piston 14 to the right, causing therol'ler 12 to engage the handle 11, swing the handleon an are thereby turning the valve stem and either partly or Wholly closing the valve 9 in the performance of aspeed diminishing or stopping operation. The rod 13 carries an abutment 147 adapted to engage a stop 148 Whiclnin turn, is adapted to be'moved into the path of said abutnientto check piston 14 in a substantially mid position ,(Fig. 2). The shaft abutmentis held doivn by a spring 152 in a cylinder 153'c'arri'edby anarm 154. n I A Associated with the valvecylinder15 are the speed diminishing valve 16and'the stop valve 17, the latter ot' which has adirect connection to the main air brake line .18, the

.former having a branch connection '19 to the brake llne. The mam speed dim nishlng valve 16 has a m 1n ute exhaust orihce 20, while the main stop valve 17 hasan exhaust orifice 21 oflarger proport1 ons. These valves comprise disks 155 and 156 whichrespectively, Work against partitions 157 and 158, suitable ports or passages beingtormedineach to control the passage of air upon turning of the disks by the associated motors.

Upon the opening of the diminishing valve 16, the air from theair brake line 18 escapes very slowly and causes a gradual application of the brakes. It is through the agency of the valve 16 that the speed of the engine and train is diminished. U'po nope ning the main stop valve 17 air Lrom the main air brake line 18 escapes morerapidlythan it would trom the valve 16,res'ulting in a positive application otthe brakes and the total stopping of the engine andtrain.

The stem 22 of the speed diminishing valve 16 carries a quadrant 23 in enga 'ement with the pinion 24 of a motor 25 W ich is normally energized to hold the valve closed against the tension of a spring 26. Similarly, the stem 27 of the main stop valve '17 carries a quadrant 28 engaged by the pinion '29 of a motor 30 which is normally energized to hold the valve closed against the tension of a spring 31. n

SteamtrOm the chest 7 has permanent access to the steam cylinder 32 through a pipe 33 and tends to raise the. piston34 against the tension of 'a spring 35. This spang bears on the piston 36 in a regulating cylinder 37. The two pistons are connected by a rod 38 which also carries a D or slidevalve 39. This valve controls the opening of an exhaust 40 and is adapted to uncover a regulating air pipe 41. I

A. pipe 42 conducts compressed air from a reservoir 43 to the regulating cylinder 37.

'tion from the br'a-ke line 18 and compre.

As long as the regulating valve 39 remains in position (Figs. 1 and 2) to uncover the inlet to the pipe 41, air under pressure from the reservoir fills said pipe and its branches 44 in turn keeping the pistons 45 and 46 of the automatic opening valves 47 and 48 raised so that air from the brake line 18 may have access to the diminishing valve 16 and that will remain in the "uncovering position so that air under pressure from the reservoir 43 will constantly be present in the valve "casings 16 and 76 'Whiletlie engine is in the normal running condition.

Should the engineer, upon approaching a semaphore displaying a cautio-n signal, re

duce the tl o w o1 steamto the chest 7 the a 1 ton 34 and slide valve 39 will ace-:nrdingl fall so that compressed ail-to thepipe 41 is cut ofl. This results in the pistons 45 and '46 falling'so that'the valves 50 and'51 which a'recarried thereby, will sever connnunicaed air pipe 49 respectively, and then when the arn'iature reaches a vacancy in the diminishing magnet series 53 (Fig. 2) as will be described later, the opening oi the circuit embracing the mot or 25 of the valve 16 and motor ot the valve 76 will have no eiiect through the tfunctionot either valve 16 '76. The magnet series 53 is intended solely for the amature The loss oi compressed airat the valve 16 is thereby avoided and furthermore, the piston 14 1S prevented 't'roin fuctioning to partially close the main valve pipe 41 and air under pressure holds the pistons 4-5 and 46 up. Now, when the engineer reduces the "steam pressure in conformity with a caution signal, the piston 34 recedes and causes the regulating valve 39 to cover the entrance to pipe 41; in "tact. bridge said entrance and the port 40. thus permitting the'air that was holding the pi tons 45and 46 up, to escape to atmosphere. Said pistons being relieved of pressure. will be forced down by the springs to close the valves. r

The armature which may be conveniently distinguished by calling it the speed diminishing armature, carries a plurality of electro-magnets 55 which are perpetually enllll ergized by current from a battery B from which the current is conducted by wires 56 and 57. One end of the armature is hinged at 58 in the casing 59, the other end having connection at 60 with an arm 61 which carries a switch 62 controlling the passage of current from the battery B to the motors 253 and 54 via wires 63, 6 1 and 65. The wires 63 and 65 and the co-ntinuations thereof beyond the switch on are connected to separate contact segments 66, 67 and 68, 69 (Fig. 5).

The switch, generally designated 62, is composed of pairs of contact rollers '70. 71

and 72, 73 which, together with the switch arms upon which they are mounted, are in tended to complete the current paths of the wires 63 and 65 when the armature 52 is down and the electro-magnets 55 are attracted by the speed diminishing track series 53. The aforesaid switch arms are of a resilient nature so as to press the rollers against the contacts, and in practice, springs, such, as seen in Fi 6, may be added to insure a thorough contact. The series of speed diminishing magnets 58 extends throughout the entire length of the railroad, being disposed on the outside of the rail 74, and it is only at such special points as crossings (Fig. 3) etc. that sections of said series are omitted.

When the armature 52 encounters one of these vacant places in the speed diminishing track series 53, the electro-magnetic attraction ceases at once, a weight 75 on the arm 61 then causing the armature 52 to rise (Fig. 2) and the switch 652/ to be opened. This results in the deenergization of the motors 25 and 5 1 and the consequent opening of the diminishing valves 16 and 76 with this result: air from the brake line 18 gradually escapes at the orifice 30 of the valve 16 and causes a slow application of the brakes, and air from the reservoir 13 passes through pipe 49 and valve 7 6 to the pipe which leads to the left end of the valve cylinder 15. Before reaching the valve cylinder .15, the air in pipe 80 must pass through a cylinder 1 19, the automatic closing valve 77 and a back check valve 78. Air, in enterin the cylinder 1419, causes the piston 150 suuated therein, to elevate the stop 1418, against the tension of a spring 1.51. The piston 1470 must first rise before the air can pass into the pipe 80 and to the other elements noted. The cylinder 14-9 has an arrangement of suitable vents function ng both on the rise and fall of the piston.

A partial closure of the main steam valve 9 is accomplished by the movement of the piston 14 toward the right in the cylinder 15. This movement, in turn is accomplished by the air under pressure which is admitted by the pipe 80. The rightward movement of the piston continues until it is arrested by the engagement of abutment 1 17 with stop 1 153 and the inlet to the pipe is reached. Thereupon, some of the compressed air flows through the pipe into the casing 8d of the automatic closing valve 77, forcing the piston 88 down so that the valve 77 closes the pipe 80. The pipe 85 is made considerably larger than the other pipes (80 for example) so as to insure the prompt eduction of the air from the cylinder 15 on the operation under consideration.

Depression of the piston 88 continues until vents 139 are uncovered, whereupon the air at the left side of the piston escapes to atmosphere, the piston 14: having been stopped by the aforesaid engagement of the abutment 1417 with the stop 148. This occurs immediately at the right of the entrance into the pipe 85. A spring 1&0 tends to force the piston 88 upwardly to again open the valve 77, but this tendency is checlted by the action of a vacuum valve 1 11, so-called on account of the action that occurs within it.

This valve, a detail of which is shown in Fig. 8, has a hinged shutter 142 provided with a fine aperture 14-3. The valve is hinged so that it opens upon the depression of the piston 88 and permits the air beneath the piston to be forced out. As the piston :38 begins its return movement by virtue of the pressure of the spring 140, a tendency toward the formation of a vacuum in the lower part of the cylinder 84 will be eX hibited, which vacuum, if complete enough, would serve to hold the piston in an approximately stationary position. However, the fine aperture 143 lets a line stream of air through so that the piston 88 rises very slowly, the rate of said sliding movement being so slow that by the time the valve W opens again, adjustments will have been effected to again close the prin'iary diminishing valve 76 or close the automatic opening valve 51.

A. similar baclt check valve 79, but opening in the direction opposite to that of the valve 78, is situated in the continuation of the pipe 80 and adjacent to the place where this pipe joins a con'iprcssed air pipe 110. The pipe 110 continues on around and en tore the piston chan'iber 81 of another auto matic closing valve 82, the gate 83 of which controls the passage of air from the cylinder 15 to the piston chamber 84- oi the first automatic closing valve T7 via pipe 85. Like the valve 82 the valve 77 has a gate 86 and the gates 82% and 86 of the respective valves are carried by pistons E57 and 88 so that air entering the respective piston chambers n'iay act thereon and cause a closure of one or the other of the two valves.

The pipe 1110 leads from a primary stop valve 109 to the other side of which a branch 89 leads from the compressed air pipe 49. The valve 109 is constructed and operated similarly to the valves 16 and 17. The stem 90 of this valve carries a quadrant 91 with which the pinion 92 of an electric motor 93 engages. This motor and the motor 30 of the main stop valve 17 areembraced in a circuitincluding wires 94, 95 and 96 these wires beingcontrolled'by a switch 97wl1ich is constructed on precisely the same order as the switch 62, details otwhich are disclosed in Figs. 1 and 5. The switches 97 and 62 are separately operatedby the respective track magnetseries 102 and 53.

Current for the operation of allof the motors represented, is drawn from the wires 56 andb'l' which in "turn lead to the battery 13. The battery is adapted to be charged by the'generator G, but in practice bothmaybe replaced by a turbo-generator which will be started before the train leaves, and will furnish all necessary current. This battery also supplies current for the perpetual energization of a plurality of electro-magnets 98 on an armature 99 which, because ott'its function, may suitably be designatedthe stop armature. This armature is hinged at 100 inside of a casing 101, and as long as the stop magnet series 102 (inside of the rail 74) remains energized, the armature 99 will remain down and the switch 9? closed. The magnet series 102 is intended solely for the arn'iature 99. The casings 59 and 101. are respectively hinged at 59" and 101 so that-they may readily be raised for inspection. In practice, eaclrcasing will be turished with anon-magnetic bottom in winter to close the opening shown and so keep out snow, etc.

But as soon as the tram reaches a block having a danger signal set against it (Fig.-

9) the armature 99 will encounter a deenergizcd sectionof the stop magnet series 102, whereupon the weight 103 will elevate the armature and open the switch 97 so that the motors 30 and 93 become deenergized and the stop valves 17 and 109 will open. The circuit which energizes the magnet series102 is broken when the arm 128moves upon the insulation 124. The energizing circuit is completely traced farther down in the description. Upon the happening of the foregoing events, air from the brake line 18 will rapidly escape at the orifice 21 of the stop valve '17 and cause a prompt application of the brakes. At the same time, air from pipe 49 will pass through the primary stop valve 109 via pipe 89, pass through pipe 110, past back check valve 7 9 and enter the left end of the valve cylinder 15. The weight- 103, like the weight 75, is movable between suitable stops within the respective casings, the lower one being adjustahle as shown in each case to vary the rangeof motion of the armatures and conse quently govern the action of the associated switches.

Naturally, the air from pipe 110 will also enter the piston chamber 81 of the automatic closing V21'lV'82 t11(l cause the gate 83 of that valve to close th'e pipe 85. This pipe has con'imunication' with the cylinder at a point approximately midway of its length. and it is obvious that if the pipe 85be closed, no air can escape and-the piston l%l;\vill be "forced to make the full length of its stroke in the cylinder 15. The back check valve 78 prevents air froinreaching the e -,'li-nder 1 l9 so that thestop 14:8-will not-be raised to obstruct the abutment 1 .7. This will cause the complete closure ofthe steam valve 9 through the agency of the roller 12 and arm 11, so that the engine will be brought to a stop. The piston chamber 81 has a vacuum valve 14:5 in a very fine air vent 116'. The ventu146 and the vent 199 of the valve 141 do not function alike, the latter permitting a prompt eduction ot-air, thet'ormer merelyrelieving any compressed air that might be caught in the pipe 110 after valve 109 has closed, thus making sure that valve 82 assumes the open position.

The free and unobstructed passage oi the piston 14- to tlurrig-ht ofthe valve cylinder 15 necessitates the provision of avent 105 which, beingin the nature of avalve, may be constructed to operate like any spring poppet valve until it is desired 'to return the piston to the original position at the left end of the cylinder. At such time, the stem must be screwed down until: it engages the valve so that pressure from within cannot cause it to open. When the train again enters a clear block in which the magnet series 102-is energized, the resulting attraction of the armature 99 again closes the switch 97 so that the motors and 93 become energized. The valves 17 and 109 thereupon close, cutting off the air from reservoir 43 to thelcft end of the cylinder 15. The piston may then be returned by opening a valve 106 to admit air from the reservoir 48 to the rignt of cylinder The pressure of air required to return the piston '14; is not very great, and in order to prevent the cscape'ot air at the vents 199, these vents are provided with flaps 14-1: which may be held closed by. the hands until the piston has returned to the original position in Fig. 1. It is necessary to open a vent valve 159 at the left of the cylinder 15 so that there may be no compression of air ahead of the piston.

Provision is made for the opening of the valve 9 upon recession of the roller 12, as when the piston 14: returns to the normal position, and in the event of a breakage of the arm 11. This provision consists of a spring 108 wound round the stem 10 of the valve and secured in such a manner as to cause the opening of the valve 9 under the conditions named.

All important pipes, such as the brake line 18 and the compressed air pipes 12 and 49, have valves 112 which not only are intended to normally be opened, but are provided with locks 113 by which they are locked in the open position. Attention is now directed to Fig. 8 which is a diagrammatic representation of enough of a railroad to show how the three blocks A, B and C are protected.

There is a semaphore such as 11 1, 115 and 116 at the beginning of each of the respective blocks. Each of these semaphores controls the speed diminishing and stop electromagnets 53 and 102 in the blocks behind it. The details of construction of one of these semaphores is illustrated in Figs. 6 and 7.

The casing 117 of the semaphore 11a (for example) has an internal base of insulation 118 upon which a pair of contact members is mounted, one being composed of contact sections 119, 120 and 121 and adapted to control the speed diminishing magnets 53 in the block behind, the other pair being composed of contact sections 122, 123 (Fig. 3) and adapted to control the stop magnets 102 in the same block.

Fig. 3 shows these pairs of contact members as being developed along the dot and dash lines representing the shaft 12 1. The reader will understand that both pairs of contacts are arranged around the shaft 124: as are the contacts 119, 120, and 121 in 6, and as shown more particularly in Fig. 7. The shaft 124 of the semaphore switch carries an arm 125 which has a pair of contact rollers 126 and 127 to engage the con tacts 119 etc. of the first pair, and a similar arm 128 with a pair of rollers 129 and 130 to engage the contacts of the other pair. The rollers are held in contact with said pairs by springs 131 and 132.

The block preceding the block A is clear, and by virtue of the semaphore 114 being in the erect position (Fig. 3), the magnets and 102 of the speed diminishing and stop series are energized so that the train may proceed over the track according to the normal operation. The circuit by which these magnets are energized is as follows: Current flows from the generator G to the common wire 160 where it divides, a portion flowing to the contact 119, across arm 125 to the contact section 121, over wire 13 1 to the track magnets 58 whence it returns to the generator via wire 135. The current also Hows to the contact 122, across arm 28 to the contact 123, over wire 137 to the track magnets 102, returning to the generator via wire 136. The erect position of the semaphore 114 also indicates that the block A (which it precedes) is clear.

The block A is clear, so far as the track is concerned, with the exception of the presence of the crossing which will require a diminution of the speed either by manual or automatic control. A section of the speed diminishing magnets approaching the crossing is shown omitted, the result of this omission being to cause the deenergization of motors 25 and 54 (Fig. 2) when the train enters block A. The magnets and 98 associated with the diminishing and stopping armatures and 99 are wound so as to exhibit south poles, while the magnets of the speed diminishing and stopping series are wound so as to exhibit north poles.

The normal energization of the various sets of magnets causes an attraction which is necessary to the proper operation of the apparatus and obviously when any one track section is d-eenergized or is partly omitted as in the case of the speed diminishing magnets of block A, there will be an. operation of one or the other of the two armatures 52 and 99 due to either an actual cessation of magnetic attraction or an entire absence of attracting magnets. The result of the latter instance in respect to the armature 52 upon entrance of block A by the engine is illustrated in Fig. 2.

Assume now that the semaphore hasbeen moved to the caution position as, for example, the semaphore 115 at the beginning of bloc-lcB. The switch arm 128 still bridges r! the contacts 122 and 123 so that the stop n'iagnets of block A are still energized. The switch arm 125, however, assumes the position where the upper roller 126 engages a section of insulation, thereby breaking the circuit which embraces the speed diminishing magnets '53 of block A so that these magnets become deenergiz ed. Upon the approach of the train the speed diminishing armature 52 will be released with the result that-the diminishing valves 16 and 7 6 will open, the brakes gradually be applied, and the flow of steam to the chest 7 diminished.

Assume next that there is an obstruction in block C so that the semaphore 116 is set at danger. The switch arm 128 has now moved to a position where one of the rollers 129 engages an insulating section with the result that the stop magnets 102 of block B are deenergized. Upon approach of the train, the stop armature 99 will be released, the air brakes will be promptly and fully applied, and the flow of steam to the chest 7 cut oil entirely. The speed diminishing magnets of block B will become reenergized because of the engagement of the roller 126 with the second contact 120 which has a connection 188 with the wire which leads from the contact 119 to one side of the generator 133.

lVhile the construction and arrangement of the improved train control as herein de scribed and claimed, is that of a generally preferred form, it is to be understood that modifications and changes may be made without departing from the spirit of the invention or the scope of the claims.

I claim 2 1. A train control comprising a series of el-cctro-magnets extending the full length of a track excepting a place desired to be protected .41 signalling device having associated means to normally energize said electro-magnets, a steam valve, means adap'ed to operate the steam valve, means to control the operating means, and normally energized electro-magnetic means included in said control means held attracted by the series of electromagnets to restrain the ac tion of the control means until said pro-- tected place is reached.

2. A train control comprising a series of elcctro-magnets extending the full length of a track et-rceptinp; a place desired to be protected, a signalling device having associated means to normally energize said electro-magnets, a steam valve. means adapted to operate the steam valve. means to control the operating means, normally energized electromagnetic means included in said con trol means held attract-ed the series of electromagnets to restrain the action of the control means until said protected place is reached, and means associated with the steam valve operating means permitting only a predetermined degree of operation for the partial closure of the steam valve.

- A train control comprising a track series of electro-magnets extending the full length of the track excepting a place desired to be protected, a signalling device having associated means to energize the track series of eleetromagnets while in a safety position, a train carried steam valve, means adapted to operate the steam valve. means to control the opcrting means, and movable eleetro-magnetic means included in said control means held in an attracted position to restrain the action of the control means while traversing the track series of eiectromagnets but moving to a released position upon reaching the protected. place thereby initiating the functions of the control and valve-operatiim' means even though the signalling means still assumes the safety position.

-'l-. A. train control comprising a track se ries of elcctro-magnets extending; the full length of the track excepting a place desired to be. protected. a signalling device having associated means to energize the track series of electroinaenets while in a safety positiom a train carried steam valve. means adapted to operate the steam valve. means to control the operat'ng means movable electroanaonetic means included in said control means hole in an attracted position to restrain the action of the control means while t'aversing the track series of electromagnets but moving to 21 released position upon reaching the protected place thereby initiating the functions of the control and valve-operating means even though the signalling means still assumes the safety position, and means associated with the operating means permitting: a limited operation and therefore a partial closure of the steam valve.

5. A traincontrol comprising a track so rics of electro-magnets extending the full length of the track excepting a place dcsired to be protected, a signalling device side the track having associated means to energize the track series of elcctronmc'nets while in a safety position. an engine-carried steam valve means adapted to operate the steam 'alve, means to control the operating]: means. electron'iagnetic means included in said control means assuming an attracted position While traversing the track series of electromagnets, and means to retract said electromagnetic means upon .l'CflCl'llDQ' the protected place and initiate the functions of. the control and valve-operating means even though the signalling device still as sumes the safety position.

6. A. train control comprising a track series of electi'o-magnets extending; through the length of the track evcept-ing a place desired to be protected, a signalling device having associated means to energize. the track series of electromagncts while in a safety position. an engine-carried steam valve. means adapted to operate the steam valve. means to control the operating means. movable electro-magnetic means included in said control means assuming an attracted position while traversing said track series of electromagnets. means including a weight for shifting said electric-magnetic means when the latter passes beyond the influence of the track series of electromaojiiets in said protected place. and associated switch means actuated upon said shifting to initiate the function of the control means and thcreb set the valve-operating means in motion.

7. A train control comprising a series of track electro-mapgnets extending over the length of a track excepting a place desired to be protected. a signalling device having means for energizing thetrack magnets While in a safety position. an engine-carried steam valve. means adapted to operate the steam valve. means to control the operating means. a movable armature included .in said control means assuming: a attracted position while traversing the track magnets. a switch associated with the control means. a member which is movable with the switch and has connection to the armature. and means causing said member and switch to shift when the armature moves beyond the influence of the track magnets into said protected place and thereby assumes a released position to initiate the function of said control means and start the valve operating means in motion.

A train control comprising manual and automatic engine-carried steam valves, means adapted to operate the automatic steam valves, means controlling the operating means, a series of energized electro-magnets extending along a track excepting a place desired to be protected, train-carried electromagnetic means included in said control means attracted into one position by said series of track electromagnets until the protected place is reached and thereupon released into another position to initiate the functions of the control means and cause a partial closure of the automatic valve through said operating means, and means associated with the manual valve preventing said functionof the control means by said release of the train-carried electro-magnetic means when the manual valve is operated prior to reachingsaid protected place.

9. A train control comprising; the combination of an automatic valve with a steam pipe leading: to a steam chest and having a manual valve, means adapted to operate the automatic steam valve. means to control the operating means, a series of energized track electro-magne ts terminating at one side of a place to be protected, train-carried electro-magnetic means attracted into one position by said series of tracl: electromagnets and released into another position when said protected place is reached to initiate the function of said control means tor the partial; closure of the automatic valve by said operating means, and means acting; under the influence of steam in the steam chest to prevent the aforesaid functioning of the control means upon a reduction of steam pressure in the chest by an operation oi the manual valve prior to reaching said protected place. l

10. A train control comprising an automatic valve in combination with a steam pipe in communication with a steam chest and having a manual valve, means adapted to operate the automatic valve. means to control the operating means, a series of energized track electro-mag'nets terminating at a place to be protected, movable train-carried eleotro-niiagnetic means attracted in one position by said series oi trackelectroma r I nets and assuminganother position in said protected place when released from said series o't' track electioinag'nets to initiate the function oi the controlling; means for the partial. closure of the automatic valve through said operating means, means substantially occupying a predetermined position by the pressure of steam in the chest but moving from said position upon a reduction of the steam pressure by said manual valve, and means associated with said moving means to prevent the Functioning of said control means it said reduction of pressure by the manual alvc occurs before said protected place is reached.

11. A train control comprising an automatic valve in combination with a pipe leadinn; to a steam chest and having a manual valve, movable means associated with said steam chest adapted to occupy one position at a predetermined high steam pressure, instrumentalities becoming active upon reaching a protected place along a railroad to operate the automatic valve and reduce the steam pressure in the chest, and means associated with said movable means and moving with said means to another position upon a reduction of steam pressure in the chest by an operation of the manual valve prior to reaching said protected place for preventing the action of said instrumentalities when said place is reached.

12. A train control comprising an automatic valve in combination with a pipe leading: to a steam chest and having a manual valve, movable means in communication with the steam chest caused to occupy one position bv a predetermined high pressure of steam in the chest, instrumentalities becoming active upon reaching a protected place along a railroad to operate the automatic valve for a reduction of steam pressure in the chest, and means in connection with said movable means permitting the action or said instrun'ientalities while the steam remains at said high pressure but preventing); said action it the manual valve is operated to reduce the steam pressure prior to rcachina said protected place and thereby enable the movable means to take another position and carry the connected means with it,

13. A train control comprising an automatic valve in combination with a pipe l nding; to a steam chest, means adapted to opcrate said valve, a steam cylinder in com n'iunication with the chest, a piston maintaininc; one position in the cylinder under a predetern'iined hipgh steam pressure. a fluid pressure system adapted to actuate said opcrating means, and means in connection with said piston maii'itainin r said system closed and in readin v:s tor the actuation of said operating means while the steam remains at said pressure but opening said system upon a reduction of the steam pressure and consequent chamrincin position o'l said piston.

14. A train control comprising! an auto matic valve in combination with a pipe lead ing' to a steam chest, means adapted to operate the valve, a fluid pressure system to actuate the operating; means, a steam cylinder in communication with the steam chest, a piston maintained in one position in the cylinder by a predetermined high steam pressure, and valve means in connection with the piston to control said system maintaining it closed and in readiness to actuate the operating means as long as the steam remains at said pressure.

15. A train control comprising an automatic valve in combination with a pipe leading to a stea-n'i chest, means adapted to op erate the valve, a fluid pressure system to actuate the operating means, a steam cylinder in connnunication with the steam chest, a piston maintained in one position in the cylinder by a predeterminee high steam pressure, valve means in connection with the piston to control said system maintaining it closed and in readiness to actuate the operating means as long as the steam remains at said pressure, and other valve means in said system required to be operated before a continuity oi the fluid pressure will be established to render the operating means active.

16. A train control comprising a valve in combination with a pipe leading to a steam chest, means adapted to operate the valve, a system furnishing fluid pressure to actuate the operating means, means held in position by a predetermined high steam pressure in the steam chest to maintain the closure of the system, another valve in said system maintaining it open, a series of ener gized electro-n'iagnets extending along a track to a protected place, and train-carried electromagnetic means attracted to one position while traversing the track series but shifting to another position when reaching said protected place to shift said other valve for the complete closure of the system and the consequent actuation of said operating means.

17. A train control comprising a steam valve, a series of energized electrounagnets extending along a track and terminating at a place to be protected, means adapted to operate the valve, a system containing pressure fluid to actuate the operating means, a closed valve shutting ofl? the fluid from said operating means, electrical means exerting an influence to keep said valve closed, traincarried electro-magnetic means attracted in one position while traversing said series of track electromagnets and becoming released into another position upon reaching said protected place, a switch associated with said electromagnetic means and with said electrical means to interrupt the influence of the latter when the electro-magnetic means is released, and means embodied in the valve to then open it for the passage of fluid to said operating means.

18. A train control comprising a steam valve, means adapted to operate the steam valve, a system containing pressure fluid to actuate the operating means, a closed valve in said system preventing the passage of fluid to the operating means, an electrical motor exerting an influence to keep the valve closed, a series 01 energized electro-magnets extending along a track and terminating at a place to be protected, a train-carried armature attracted into one position while trav ersing the series of track electro-magnets and shifting to another position when reaching the protected place, a switch which moves with the armature and controls the motor to interrupt its influence when said armature shifts, and means to then move the valve counter to the influence of the motor and close the system for the passage of fluid to the operating means.

19. A train control comprising a valve in combination with a pipe leading to a steam chest, means adapted to operate the valve. a system containing pressure fluid to actuate the operating means, a source of fluid for said system, a valve in said system, an electric motor exerting an influence to keep the valve closed, a series of energized elec tro-magnets extending along a track and terminating at a space to be protected, an engine-carried armature attracted into one position while traversing said series of electromagnets and shitting to another position upon reaching said protected place, a switch moving with the armature to control said motor and causing an interruption of said influence upon shifting of the ar iature and permit opening of the valve for the passage of fluid to the operating means, and means interposed in said system between the valve and the source of fluid and adapted to be held in a predetermined position by a predetermined pressure of steam in the steam chest to maintain the continuity of communication.

20. A train control including a steam valve, means to operate the steam valve, means to supply pressure fluid to actuate the operating means, and means which is subjected to the pressure of said fluid upon a predetermined amount of actuation of said operating means to cut ofl" the flow of pressure fluid so that the steam valve is but partly closed.

21'. A train control including a steam valve, a cylinder having a piston with connections to operate said valve, means to conduct a pressure fluid to the cylinder to actuate the piston, normally open cut-ofl means in the fluid conduit. and a pipe leading from a predetermined place in said cylinder to the cut-oft means to conduct some of said fluid for the operation of the cut-oft means when said pipe is uncovered by the piston.

22. A train control including a steam valve, a cylinder having a piston with connections for operating the steam valve. means to conduct a pressure fluid to the cylinder to actuate the piston. cut-ofl' means associated with the fluid conduit including a piston having a valve, and a pipe leading from a substantially mid position of the cylinder to a point of discharge against the cut-ofli piston to conduct fluid from the cylinder when the operating piston enters the entrance to said pipe for the operation of the cut-off means.

23. A train control including a steam valve, a cylinder having a piston with con nections for operating the steam valve, means to conduct a pressure fluidto the cylinder to actuate the piston, out-ofl means associated with the fluid conduit including a piston having a valve, a pipe leading from a substantially mid position of the cylinder to a point of discharge against the cut-ofl piston to conductfluid from the cylinder when the operating piston enters the entrance to said pipe for the operation of the cutoff means, and means associated with the cut-off means for relieving the fluid pressure between the cut-ofl' means and the operating piston when the cut-off piston has accomplished a predetermined movement.

24. A train control including a steam valve, a cylinder having a piston with connections for operating the steam valve, means to conduct a pressure fluid to the cylinder to actuate the piston, cut-ofl means associated with the fluid conduit including a piston having a valve, a pipe leading from a substantially mid position of the cylinder toa point of discharge against the cut-off piston to conduct fluid from the cylinder When the operating piston enters the entrance to said pipe for the operation of the cut-ofl' means, means associated with the cutoil means for relieving the fluid pressure between the cut-off means and the operating piston when the cutoff piston has accomplished a predetermined movement, means to return the cut-ofl piston and associated means retarding the return of said piston to prevent a premature opening of the cut-off valve.

25. A train control comprising a steam valve, means to operate the steam valve, a conduit leading pressure fluid to the operating means for the actuation thereof, a primary valve adapted to be opened to let the fluid through for the actuation of said operating means, a secondary valve caused to close the conduit after a predetermined actuation of the operating means which operation partially closes the steam valve, and means which is responsive to a reduction in steam pressure attending said partial closure to again close the primary valve and prevent access of the fluid to the operating means even though the secondary valve should open.

26. A train control comprising a valve in combination with a pipe leading to a steam chest, means adapted to operate the steam valve,a conduit for leading pressure fluid for actuating the operating means, a primary valve in said conduit adapted to be opened for the passage of fluid and the actuation of the operating means to partly close the steam valve, a secondary valve controlling said conduit toclose it upon a predetermined actuation of the operating means representing said partial closure of the steam valve, a valve associated with said primary valve keeping the conduit open to the primary valve, and means associated with the steam chest acting upon a fall of pressure therein to cause the closing of the associated valve and prevent fluid from reaching the primary valve.

27. A train control comprising a valve in combination with a pipe leading to a steam chest, means to operate the steam valve, a

pressure fluid system to actuate the operating means, valve means to control the flow of fluid into the system, and means associated with the steam chest and with the system adapted to sever the fluid flow before it reaches the valve means upon a drop in pressure of steam in the chest.

28. A train control including a steam valve, means adapted to entirely close said valve to stop the flow of steam, means for conducting pressure fluid for the operation of said means, means in communication with said conducting means making use of a part of said fluid to interpose an obstruction to said closing means and thereby permit but a partial closure of the valve, and means associated with said closing means permitting an exhaust of the fluid when thus obstructed and also cutting off the flow of fluid in said conducting means.

FRANK TALLIAFERRO KNIGHT. 

